The stamp was designed, printed, and
distributed to 305 post offices across the
United States in secret. The postmasters did
not know what the stamps were or resembled
until official word was sent to unseal the
packages and begin the distributions and sale of
the stamps.

The Project Mercury stamp was released for
sale at 3:30 pm upon the spectacular mission
and successful splashdown of the astronaut,
John Glenn Jr.

Only the Cape Canaveral Florida postmark has
the words "First Day of Issue" in its cancel. This
is considered the official cancel.

Any recovery ship cover with a February 20,
1962 postmark and a "Project Mercury" stamp
is a backdated cover. There were no stamps
aboard any ships.